FILE - In this Tuesday, Jan. 29, 2013 file photo, a man wears a mask on Tiananmen Square in thick haze in Beijing. China, one of the most visited countries in the world, has seen sharply fewer ... more 
FILE - In this Tuesday, Jan. 29, 2013 file photo, a man wears a mask on Tiananmen Square in thick haze in Beijing. China, one of the most visited countries in the world, has seen sharply fewer tourists this year, with worsening air pollution partly to blame. (AP Photo/Ng Han Guan, File) less 
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Associated Press | Photo By Ng Han Guan, File
Tue, Aug 13, 2013 3:05 AM EDT